Posted
by
samzenpuson Wednesday January 30, 2013 @08:00PM
from the doom-and-gloom dept.

Lasrick writes "Dawn Stover has another great piece detailing why renewable energy will never provide us with all our energy needs. She deconstructs the unrealistic World Wildlife Fund report (co-written by several solar companies) that claims renewables will be able to provide 100% of the energy needs of several countries by 2050. From the article: 'When renewable energy experts get together, they tend to rhapsodize about the possibilities, believing that this will somehow inspire others to make their visions come true. But ambitious plans to power entire countries on solar energy (or wind or nuclear power, for that matter) don't have a snowball's chance in Australia. Such schemes are doomed to fail, and not because of the economic "reality" or the political "reality" -- however daunting those may be. They are doomed because of the physical reality: It's simply not physically possible for the world's human population to continue growing in numbers, affluence, and energy consumption without trashing the planet.'"

Most of the world is heading in a few more years to being able to make solar power more cheaply than getting power from the grid (the parts that are not already there, like much of India).

I'm all for living within our current energy means in a reasonable way (and I abhor the pollution from mining and burning coal and oil), but she cites a calculation that projects exponential growth on Earth forward a few hundred years, calculates we will need to cover the whole Earth in solar panels (and then the Galaxy), and then concludes from that somehow that we should stay the way we are. That just does not seem to be a healthy emotional space to be in.

She's probably against self-replicating space habitats that can duplicate themselves from sunlight and asteroidal ore, too? Even if it would mean quadrillions of people could live in the solar system and the survival of some aspect of humanity might be better assured? From the 1920s by J.D. Bernal on that:http://vserver1.cscs.lsa.umich.edu/~crshalizi/Bernal/world/ [umich.edu]

Maybe we should all move back to live in trees in Africa? Or maybe that is too "advanced" compared to flopping around in muddy tidal flats?

There are always at least four issues to a resource question:* How much stuff do we "want" based on cultural expectations?* How efficiently can we use what we have to make what we want?* How should we divide all that up?* How can we expand the scope of what we are doing to new types or resources or new areas to find them in?

That is the complexity of the issue and she stakes out a position without discussing the possibilities or why she prefers one over the other. There might be a case to be made in the direction she tries to go (e.g. the Amish may have an overall happier community-oriented way of life), but she did not make it.

1) If we wait for nature to turn our energy consumption into an S-curve, the process will be extremely unpleasant for the people involved (constraints due to resource scarcity have a habit of fueling some rather nasty conflicts). It seems to me that we're better served to point out the problem so that we can try to find a way to limit our own energy use intentionally so that we can do it in a less painful way.

2) Even if population growth stops, energy growth doesn't necessarily. Per capita energy use has been increasing for pretty much all of human history. And, there's no reason to think that we aren't going to keep inventing new technologies that need ever more energy. (And, I should note here that most improvements in energy efficiency work by reducing the amount of energy that goes to waste heat, not by reducing the amount of energy required for the purpose for which we're expending energy. CFLs and LED light bulbs put out the same amount of energy in light as do incandescents; but, they give off less heat, for example.) If this continues, we'll still have a problem.

3) Expanding into the galaxy still has a non-exponential limit on our growth. In that case, at best we increase the available space and energy resources quadratically, since our outward expansion is limited by the speed of light.

4) Human ingenuity does not trump physics. If there are no new energy resources to tap, no amount of cleverness will allow growth in energy use to continue. And, please note, zero point energy is not a magical reservoir of unlimited energy waiting to be tapped.

5) I don't have to believe that today's conception of physics is 100% correct (and, in fact, I can tell you with 100% certainty that our current understanding of physics is, at best, incomplete) to be extremely confident that there aren't major unknown sources of available energy that can supersede the output of the sun. I can conclude this because the only phenomena that are not fully explained by known physics are things that couple only extremely weakly to the ordinary matter we are able to exert direct control over. So, any major untapped sources of energy either don't exist or are not accessible in any practical way.

6) Even ignoring the point that cold fusion is total nonsense (fusion in general is not; but, cold fusion has been shown, time and again, to be totally unsupported by the evidence), any energy source reliant on materials present on Earth will be, at best, a temporary solution. Eventually, solar will be the only source practically available.

7) Finally, TFA doesn't need to consider "a lot more obvious possibilities" when they can all be dismissed as having far less total energy available than the sun. Maybe other technologies can allow us to use energy faster than the sun outputs for a time; but, ultimately, that's just putting off the inevitable limitations for a finite (and, frankly, surprisingly short) time, unless we learn to stem our energy use.

I get it, arguments of sacrifice sound hippy and antiquated, and I picked a couple of touchy or cliched examples. But supply side manipulation can't solve complex problems like this. If you can balance your equation by also tweaking the demand side, you suddenly have many more potential solutions that don't rely on science fiction technology for supply. Just because folk live in a world that increasingly utilizes electricity doesn't mean we actually need all of those sources around us to still maintain a high quality of living. The author points to the demand side solution herself at the end of her article. But if these arguments sound like unacceptable sacrifices to you, how would you propose altering the demand side?

The article is so bad I'm not sure it's possible to give a coherent response in it's context though, because my argument is that we don't need to alter the demand side in any of the ways that's proposed. We can expedite a natural economic reality but incentivizing energy efficient appliances, and targeting our city and community planning to try and cut down on commute times or encourage the development of new urban centres (as opposed to sprawl progressively further out from one central location).

his article is sort of an IQ test: if you agree with him, you failfor instancequote "Take solar power.... In only one hour, the sun delivers as much energy to Earth's surface as humanity consumes in a year....astrophysicist Tom Murphy calculates that, even with an annual energy growth rate of only 2.3 percent, a civilization powered by solar energy would have to cover every square inch of Earth's land area with 100-percent-efficient solar panels within a few hundred years. "

I mean, do I really have to go thru all of hte problems with this one statement ?

Tom Murphy from the superb blog Do The Math [ucsd.edu] does indeed go through all of the problems with that statement and many others, carefully analyzing about all energy sources and energy storage scheme that comes to mind. A very recommended read.

Tom Murphy is an idiot. He ignores the fact that the human population will peak in 65 years and then decline. He ignores that energy harvested in space can be used in space to refine metals so the waste heat doesn't affect the earth's heat budget. what a short sighted moron, he would predict a pregnant woman would be the size of a house in 18 months.

Dawn Stover doesn't seem to realize that a) unlimited exponential growth is untenable no matter what energy source you use and b) much of the planet is already experiencing negative growth. Virtually all of the rest is heading that way.

nonsense, human population will peak and then decline by 2075, this "exponential growth" is bullshit. There is more than enough energy striking the earth to power a civilization of less than 8.5 billion people living at middle class standards. end of argument, there is no problem except solvable engineering ones.

The summary cites solar, wind, and nuclear as not being able to power cities. This is due to the fact that cities need power when they need it, and can't wait for the power to be there intermittandly. Therefore, viable options fall under the designation "baseload" power (power that you can have whenever - and in most cases wherever), and the summary's mention of solar and wind are rightly not grouped in this category.

Incorrectly, however, the summary mentions nuclear, which is in fact a primary form of baseload power along with coal, gas, or hydro. Nuclear could, can, will, and does power entire cities, in fact, Chicago is roughly over 90% powered by Nuclear energy (rough statistic - http://en.wikipedia.org/wiki/List_of_power_stations_in_Illinois [wikipedia.org]).

I lived off grid for 2 years, then had to move back into the city... It's pretty easy, you use batteries for things like lights, and you use high-draw devices when the sun is out and giving you power. No sun, no washing machine. If you change your routine a little, you can fit into renewable energy just fine.

I'm all for R&D into MSRs / LFTRs / Thorium / Fusion, etc but let's STOP promoting the THEORETICAL capabilities of reactors that have NOT yet been BUILT & TESTED!!!

It is not merely theoretical, it is a fundamental result of the physics involved, in addition to being well demonstrated.

That one toy reactor that was built at Oak Ridge does NOT count; it only establishes that the tech is feasible.For the record, it never produced electricity and never actually ran on thorium.

Generating electricity is totally irrelevant to the operation of a reactor--heat is heat. The reactor was most certainly tested with U-233 derived from thorium. Though a thorium blanket was not present in the reactor itself, thorium breeding has been demonstrated separately, and the process is so straightforward that no one could honestly suggest that it wouldn't work when combined. Wh

It should be obvious to anyone that you can't grow society forever without hitting some limit. Whether the limit is energy, or something else is rather moot. Talk about using all the energy in the galaxy is rather overboard.

So... at some point we have to stop growth. But there is no will anywhere to do so. Only when we run hard into the limits will growth stop, and then by necessity. So, all this talk about how we must change is itself just "visionary" fluff. There isn't going to be much actionary. We can't even agree on emissions to make much progress on that. He is asking for a lot more, and thus it is a lot less likely to happen.

the nice thing about an ecosystem in a bottle is that nature self corrects on usage of resources. the water evaporates but reforms as dew, the sunlight is temporary but the only form of energy waste, as the plant parts die and are consumed by micro bacteria, which make the co2 for the plants to process.

the problem is the ecosystem in a bottle is totally ignored by many people. they cling to lies. they cheat. they rise above diseases, or pretend to. humans have clean tap water from underground aquifers. humans have plastic to wrap food in and protect it from competing life forms. if we built a dozen nuclear plants for the sole purpouse of making distilled water to feed our greed for fresh water, and thus made the earth even more inviting to symbiotic life forms (plants) we could exceed the nature easily. but atomic energy and fresh water only make the problem worse, by letting us get our glass bottle ecosystem to absurd levels of production. where nature would stop, humans would proceed. this is a problem created by humans and well known since the romans began moving water to fit their goals for life on earth. and yes atomic energy comes from stars and geothermal comes from natural thorium reactions. so there is plenty of energy but the way we use it is changing and it is scary because no one can find a state where we are 'happy' with what we've done to the earth.

The people who do the math come up with numbers around 1.5 to 4 or so billions of humans by the end of the century, simply based on the available resources like energy and raw materials by then. How we get there is left as an exercise to the reader.

Bah. It's pretty clear that population will peak at about 10B, within about 30 years. This is based on already-existing trends; much of the industrial world is already at negative growth, and we've already passed "peak child" (maximum number of babies per woman) and are basically at replacement rate worldwide, though population will continue to grow because the prior growth makes the age distribution "bottom-heavy", so we'll keep growing until we fill out the populations of older people.

Economics is 99% mass psychology and wishful thinking. It doesn't apply here; this is about physics. Show me the new technology that we can deploy within the next 20 or 30 years to save our ass and I may listen to you.

The population will decline way too slowly on the demographic path. There will be some harsh realities that'll make it decline a lot faster than you think.

We will have to replace a large fraction of our current oil consumption within 20 to 30 years. Coal is not an option since CTL emits way more CO2 than burning oil directly. We're still going to do I'm afraid.

Oil is a very different question to electricity production, and hardly intractable. Aircraft will be powered by biofuels - there's a lot of work being done on producing suitable blends from biomass to run in current generation turbines without any need for conversions.

As for light vehicles - honestly who cares? People drive their cars too much already, they'll be phased out largely by price increases leading people to walk more, use public transport more, and drive less. It'll be the least worrisome free ma

Basically all of those methods are pipe dreams. It has been shown many times by multiple scholars that there is *no* way to reach today's flow rate from oil with any kind of alternate liquid fuel. The only method that would be remotely effective to get a significant fraction of today's liquid fuel would be CTL at a huge scale, with the accompanying CO2 emissions. My expectation is that people will try that for a while in 20 or 30 years until it will become obvious that it's not feasible.

not a pipe dream, there is sufficient scrubland in the USA to grow the biomass needed for liquid fuel needs of vehicles, and the organisms to transform them into butanol or vegatable oil fat already engineered by duPont

Everything is wrong with what you have said, though this does not change your basic assumption. This is not because you are right, but only by accident. First, there is no way in which using topsoil for fuel production is not completely wrongheaded, or in the common parlance, seriously fucking stupid. Second, nothing was engineered by DuPont. The processes were conceived of at public universities using some funding from DuPont, and some public funding. We engineered those processes. Third, using switchgrass

I will be amazed if in 20 years any more than 50% of all these fiddly little generators are still maintained and working. Just look at what's left of the old wind farms in CA and HI. It would be nice if they kept them up though, to give my boy something to do when the new armies of H1B's finally take the entire tech industry back home with them.

Cover every roof in the United States with photovoltaics at today's efficiency levels and you'll generate roughly as much energy as the entire civilization consumes. And lots of places in the world have roofs other than just the United States....

But, though there's no problem with resource availability, there are two huge practical concerns. First, such a project would be massively expensive. Second, it generates electricity, which is not readily useable for transportation with today's infrastructure.

Neither of those problems are insurmountable. Though solar photovoltaics aren't cheap, they're not as expensive as many petrochemical alternatives being seriously considered, such as tar sands. That is, we might not be able to afford widespread PV adoption, true...but, if we can't afford it, we won't be able to afford anything else when the existing wells run dry.

(As a side note, we're already scraping the bottom of the oil barrel. Remember Deepwater Horizon? Imagine you're standing on the shore of the Colorado River in the middle of the Grand Canyon. A mile above you is the rim; that's how far below the ocean surface the wellhead was. Several miles above the rim is an airliner flying past. That's how far through solid rock the well was bored before it reached the oil deposits. That's how desperate we already are today for oil...loooooong gone are the days when you had to be careful in Texas with a pickaxe lest you start a gusher. Yes, we've got lots of oil left -- about half as much as the planet's total original reserves, in fact. But -- duh! -- we went for the easy-to-get-to, high-quality half first, and what's left increasingly fits the definition of, "dregs.")

The problem with transportation fuels is more pressing. At the very least, with enough input energy, you can extract CO2 from the atmosphere and turn it into fuel (via the Fischer-Tropsch process, for example) that you can put back into a tank to burn it again, so we have alternatives. The catch, of course, is that it takes a lot of excess energy to do so, and so won't be cheap.

TL/DR: Yes, we can run our society on solar power. No, it won't be cheap. No, we won't have any better alternatives. Yes, that means we're facing some tough times in the not-too-distant future.

Cheers,

b&

P.S. Even worse than the looming transportation fuel shortage is the looming petroleum-based fertilizer shortage. That double whammy is going to result in lots of people starving to death. b&

Don't have exact numbers, I was led to believe that, as the price of oil increases, it would become cost-effective to extract large amounts of oil from currently known locations that are simply not cost-effective to extract at today's prices.

You are saying the same thing. Think about what "become cost-effective to extract large amounts of oil from currently known locations that are simply not cost-effective to extract at today's prices" really means. It means that the cost of oil has become so high that even silly sources are profitable. The kind where you spend 19 barrels of oil worth of energy to extract 20 barrels of oil. We are rapidly approaching the really crappy end of that bell curve.

If we can reduce the energy consumption of a device, it just means we get to use that energy for other devices, potentially more powerful.Consumption of energy will still increase even if devices are made more energy-efficient.

That's a possibility. Another possibility is that there are only so many devices needed by a person.

Pervasive robotics is the only thing that could create a change in that model.

Anecdotally I've reduced the number of devices and increased efficiency over time. I've done that while adding four people to my family. That won't hold true for long as my children grow but gone are the days of having a device for everything. Now they are all combined into just a few high efficiency devices. A smartphone, laptop, tablet and TV are all that is needed. The TV is only used a few hours a day by the kids which will get less and less as they become more independent and social life takes over.

So fewer devices, more efficient energy use - even the appliances are far more efficient and really how many refrigerators can you use? Washer dryer? Dishwasher, vacuum cleaner, toaster, microwave, coffee maker. The list isn't that long and you soon run out of things to buy. Sure you upgrade for efficiency or features every 4-5 years but you just don't buy two coffee makers anymore, you get a Keurig and make a cup at a time regular or decaf or special roast or tea.

This trend will continue. The big cost is in the manufacturing of new stuff though. That's where the robotics make a difference in a good way (discounting the labor competition) as they are far more efficient than people. They can run at off peak hours, don't require lighting (infrared would work fine), dont need creature comforts or heated work spaces.

So if we can mature past the wealth based society, robots can do all the work and we'll have plenty of energy for strategic and creative pursuits.

It's correct that we can't meet our growing energy demands with renewables. But to limit energy supply is also a dumb idea.

People really should stop worrying so much about it. We can meet our energy demand for the foreseeable future with nuclear, and nobody can tell what the world is going to be like 50-100 years from now anyway.

This is a classic case of weighting down an opponent's thesis with extra assumptions, and then using those assumptions to shoot it down.

The basic question is, "is it possible to meet the world's current energy needs using renewables?"The question the author is answering is, "is it possible to to meet the world's energy needs using renewables, assuming continued exponential growth forever?"

The answer to the second question is obviously "no", unless you're an economist. But the author only attacks the "exponential growth forever" idea, and says nothing about the first question, which is far more interesting.

*nods* yeah, the assumption at exponential growth is mandatory really seems to have gotten embedded in the economist culture, even though the models really do not support it. Exponential growth is only necessary if, well, you want exponential growth. The arguments in its favor tend to be rather cyclical and reduce to 'people will always want more, and the social circles we are part of depend on the idea that anything other then bigger numbers is personal failure'.

No. The current status of renewable energy (geothermal, hydroelectric, wind, solar, etc.) can in no way support our current consumption habits.

Can a more widely implemented renewable energy/less-polluting energy infrastructure support a society that uses less energy? Likely. Or some of us are going to have to die to make room for the bigger consumers lest we all die.

The plan?

(1) Assume all fossil-fuel-burning energy plants will shut down in 50 years.(2) Begin plans to install the most regionally appropriate renewable energy power plants to support those areas.(3) Calculate the energy shortfalls and make plans to supplement with the most reasonable nuclear options (insert arguments about recycling waste, using thorium, etc.)(4) Select a demo site, implement, learn, discuss, implement better.

I do not think it means what she thinks it means.
Her argument seems to come down to people will use all the energy they can and thus renewable will never work by simple virtue of other methods existing.

The absurd comment about...with an annual energy growth rate of only 2.3%... reminds me of the population growth people a couple decades back who claimed that if the population keeps growing at this rate, by blah-blah-blah date the population of earth will be expanding at the speed of light.

Conclusion, population will not continue to grow at that rate, energy growth will not continue perpetually at 2.3%.

Of course we may want to influence *how* things stop. Stopping a car by applying the breaks is generally preferred over accelerating full-speed into a cliff.

"Since population growth and per capita economic growth are dependent on ever-increasing energy consumption, it is physically impossible for renewable energy to provide an indefenite supply of unlimited energy. Therefore, demand reduction is the only really-long-term answer."

While I actually agree with this position, it's freaking worthless. First off, the author's argument and the WWF paper are speaking to entirely different time scales. It's functionally equivalent to saying we shouldn't waste time advocating the use of seat belts because they don't protect pedestrians. Scope matters!

The second and larger issue here is that her counter-argument is just as reality-deprived as she claims the WWF paper to be. In her conlcusion, she states simply, "To which I say: Why don't we just not do it?" i.e. why don't we exert self-control as a species and stop growing. Stop adding to total population. Stop increasing per capita consumption. It simply doesn't matter how true that is on paper. I find it amusing that she name checks the Do the Math [ucsd.edu] blog which has been linked on Slashdot previously. The blog is compelling and well-written. It also avoids the flippant suggestion that converting to a zero-energy-growth global society will somehow be as obvious as a Nike commercial. The "reality check" is that the reckoning over energy consumption will be painful. Death and violence are in the cards long before equilibrium is reached. Human beings have the capacity to plan for the future and execute on those plans, but the number of years forward we are motivated to act upon have finite congnitive limits. The climate change issue is a recent-but-not-exclusive example of these limitations at work.

There is of course an amusing logical fallacy in her argument as a whole. If we are to ever reach the equilibrium she seeks, whether that is by design or through painful reaction, that equilibrium would have to be completely fueled by renewable resources, since we must eventually run out of the non-renewable ones. Doh!

Still, I'm glad this got posted to Slashdot. Undeneath her specific arguments there is a clear undercurrent. "Physicists are smarter than all the rest of you because we deal with real stuff so all of you can suck it." That kind of attitude definitely belongs here.

Oil alone accounts for 160 exajoules of the world's energy budget a year (about 30 billion barrels of oil - a year). The book referenced in this wikipedia entry ( http://en.wikipedia.org/wiki/Cubic_mile_of_oil [wikipedia.org] ) explains it in terms that are easily understandable. Google and a calculator should do the rest.

We're literally out of gas by 2100 or thereabouts (Russia might still be fracking useful quantities but nobody else will be). While there will still be coal, natural gas and oil here and there, there won't be enough that's cheap enough, or with a high enough net energy to support a large scale industrial civilization. After that, those of us that haven't starved will be using biomass, wind, solar and hydro because that, as they say, will be that. There will. however, be many fewer of us to use it. Perhaps a LOT fewer, depending on how enthusiastic we are with nuclear weapons as tools of diplomacy.

Once upon a time, before about two and a half centuries ago in point of fact, renewable resources did provide all of our energy needs. They kept our shelters warm enough to fight off hypothermia--our most important need. They allowed us to grow our food with the aid of solar powered animals--our third most important need. And with that food we had strength and energy enough to do what was necessary to secure clean water sources and/or make alcohol--our second most important need. So if survival of the species is what is meant by "needs" here, then experience would show that the answer is yes. Certainly, the renewable resources still retained scarcity enough to justify killing one another, as though we needed an excuse, but that has and always will remain true even when we are awash in cheap energy, massive industrial capacity, and so much food that price supports are used to ensure farmers have enough money to eat. But our species needs for survival were met by renewable resources.

But if "needs" is expanded to include everything we now do with the large quantities of cheap solar energy stored in fossil fuels, then the answer is no. We once had solar powered vehicles and farm equipment: i.e. horses, mules, asses, camels, and oxen. But since we want to go further in a day than those solar powered vehicles can take us--and most of us in the developed world, myself included, often need to do so in economies structured as ours--then we now seem to need non-renewable resources.

This is question begging. It will of necessity prompt debate, and that fruitless, so long as the key terms remain undefined. To define these key terms, however, may be the more uncomfortable problem. If, on the other hand, you tell me what "needs" means, then most else is simple calculation.

We simply don't have an alternative to fossil fuels that can be rapidly scaled up, doesn't require a daunting input of raw materials and energy, and has a relatively low output of air-polluting emissions.

NREL's research showed that one quad (7.5 billion gallons) of biodiesel could be produced from 200,000 hectares of desert land (200,000 hectares is equivalent to 780 square miles, roughly 500,000 acres), if the remaining challenges are solved (as they will be, with several research groups and companies working towards it, including ours at UNH). In the previous section, we found that to replace all transportation fuels in the US, we would need 140.8 billion gallons of biodiesel, or roughly 19 quads (one quad is roughly 7.5 billion gallons of biodiesel). To produce that amount would require a land mass of almost 15,000 square miles. To put that in perspective, consider that the Sonora desert in the southwestern US comprises 120,000 square miles. Enough biodiesel to replace all petroleum transportation fuels could be grown in 15,000 square miles, or roughly 12.5 percent of the area of the Sonora desert (note for clarification - I am not advocating putting 15,000 square miles of algae ponds in the Sonora desert. This hypothetical example is used strictly for the purpose of showing the scale of land required). That 15,000 square miles works out to roughly 9.5 million acres - far less than the 450 million acres currently used for crop farming in the US, and the over 500 million acres used as grazing land for farm animals.

The TL;DR version is that we could replace all car gasoline consumption in the United States with farms equivalent to 15% the size of the Sonora Desert, using land that you can't farm on anyways, which would be a 100% carbon neutral 100% solar solution.

The article also says:

Never mind the infrastructure required for transmitting solar electricity to all who need it, and storing some for a rainy day.

That is eventually the only answer things like this ever come up with. It is mainly because no one looks at the law of diminishing returns... And we get more demand, price goes and and people figure out a way to cut it... Works every time.

No, I'm not one of those people. I'm fully aware if the fiat nature of currency, and that banks create money by lending it to you primarily on their estimation of your capacity to repay it. Nevertheless, there are only so much resources available (be it gold, or oil, or brown cows that give chocolate milk) and any economic system that ignores that fundamental rule of physics is flawed.

Gold? Seriously? Are you one of THOSE people? We have a fiat currency system.

Not Fiat - more a Yugo, a Travant, or on a good day a Friday afternoon after a few too many drinks at the pub British Leyland Jaguar.International oil and resource trading in US dollars seems to be what kept it alive under Reagan and is kept the dollar going in the crash a few years ago. Once the Norwegains, Arabs, Chinese and other big movers of US dollars decide to use something else it's screwed, but since there's now obvious a

It's also not a real law - it's a heuristic leading from human behavior. There have been plenty of weird instances in human history where changes in supply or demand didn't show the expected direct influence on the opposing factor. But there aren't local exceptions to physics, and there are fewer ways to artificially manipulate the terms in global energy equations than there are in even large economies.

In a nutshell, it states that increased efficiency of a resource actually increases the depletion of said resource. e.g, as MPG of cars increases via efficiency, more people will accept longer commutes, resulting in a net increase in the use of fuel.

Solar energy is a great alternative energy source but the current technology for photovoltaic cells include too many rare earth elements that make them expensive and limit the amount of them that can be made.

Consider the amount of energy used to dig out the soil/rock that contains those rare earth minerals from the earth, the energy used to transport all the soil to the processing plant, the energy used to extract those rare earth minerals from the soil inside the processing plant, the energy used to dispose the waste materials, the energy to transport the refined mineral earth elements to yet another plant to be made into components that can be used on the PV modules, and so on...

Modern PV panels have a net positive energy budget over their lifetime.It's not always been like that, but the current generation PV panels provide 5-7 times their energy cost (deployed in at 25-40 deg latitude)That's much better than a lot of other renewable alternatives, like anything bio-.It's also better than shale oil and tar sands, the energy requirements for extracting and refining that mess is huge.

The availability of the raw materials for PV is still an issue, and probably will be in the foreseeable future (unless there is a graphene-PV or non-rare-earth thin film PV breakthrough).

Solar energy is a great alternative energy source but the current technology for photovoltaic cells include too many rare earth elements that make them expensive and limit the amount of them that can be made. If you can make solar cells out of cheaper, more abundant materials then solar becomes more likely. Or, you go back to old fashioned boiler plate tech using mirrors to concentrate the light to generate heat to create steam or melt salt. Steam can drive a turbine directly or molten salt can be used as an intermediate storage so that steam can be generated through times when the sun isn't available.

The rare earth argument never makes any sense. It's suddenly become the "in thing" to throw out "oh too many rare earth's" when anyone mentions electronics or high technology, but no one ever comments on the specifics - it's just been picked up since the China-Japan thing happened.

PV cells are predominantly thin-wafers of silicon. Doped silicon - but the dopants are not rare-earth's, they're boron/arsenic which are both very common.

Rare-earth metals are used in high-performance high-speed transistors and permanent magnet electric motors (principally neodymium in that case). They're not used to the produce the materially voluminous bulk of solar cells, although they would be used in grid-feed inverters (presuming they're the non-isolated type - which is not certain either).

Photovoltaic power remains a gimmick for people who want to be "off the grid".

That's ridiculous. I don't (necessarily) want to be off the grid.. I want the grid to be the base load, and have solar panels generating during the day and me using the grid at night or if I am using more than my panels are generating. This at least reduces the need to build more power plants. I would hope to be net zero over a year's time, but I have no idea how feasible that is. (I don't have solar yet, but intend to get it

But you seem to have missed my point: there are better approaches to solar today than photovoltaic - at least for industrial scale generation. California used to have a solar thermal plant that was base load (it would use natural gas when solar wasn't available, bu in pracice was something like 95% solar), before closing it for environmental concerns (!).

But if you just wan't to be off the grid, for the sake of being off the grid, more power to you with photovoltaic. There's vastly more energy form the Su

As someone else said, the world simply doesn't have the resources to allow everyone to live a US lifestyle. Let alone if we top 10 billion population. It certainly has geo-political implications, but not being able to power the planet via solar due to lack of energy isn't one of them.

Also, factor in improvements in efficiency of all of our gadgets. We're not using nearly the amount of power we'd expect with the additional people in the last 30 years. And we're doing more with that energy as well. I

Stars and supernovas aren't quite a renewable resource, except possibly through initiating a new "big bang" and rebooting the universe. The universe ultimately uses energy and moves to increased entropy. New stars are formed, but the pool of matter and energy to form them from is limited; some is lost over time (think of loss to black holes, for example... no real way to recover matter once it reaches that state.)

If renewable energy doesn't exist, then the whole premise that any civilization--human or

Interesting statement, but I'll take your example a bit further. Until the last 100 years, we did not need to burn billions of gallons of petroleum products to have energy. We made due with wind and water for the most part. Even solar power was used, as houses and water were heated during the day to use "warm" at night.

The convenience of Oil in the 20th century made it the primary source of energy. It's was not the "only" source mind you, but it became the primary source. We used the convenience of Oil

Your question is making an absolutely false assertion. Population can scale down naturally. It already is in Japan, and the US (which had negative growth last year for the first time in history). Many other countries have seen negative growth recently as well.

Simply educating people should be enough. Society has done a pretty decent job of governance in the passed, without any single person making a "you live and you die" type list.

When John has 9 kids and the town makes him move away (shunning him and

Nah, the silly cynical tit didn't take into account; falling prices, increasing production, new tech to come, new manufacturing methods or anything that might've supported a position outside her tiny little mind.She could've lived a century ago and slammed rollouts of coal fired generators producing electricity in rural areas.Just another attention whore failing to make any REAL impact with her degree.Nothing to see here, just a troll with a blog. Big Whoop!

You are a dolt, I know you are anonymous but please never post such idiocy again. I'm not going to defend the Agenda 21 comment, but will attack your Capitalism comment. Go read a book and learn something about economics. Every economy works where no income = no purchases. There is not a single exception to the rule going back to the bartering days. And don't even start with the Welfare check bullshit that normally follows. Welfare would still be money in exchange for goods, but the source of money would change.

Funny that Karl Marx and the rest of the Communist bunch bickered about how bad Capitalism was.. and look how they operate? With currency in exchange for goods. The difference is that of course "The Party" controls what goods are available and who can get what goods. But the use of money works the same. It is a requirement for any economy. And be honest. Communism and Party control is way more unfair than "Capitalism" (assuming Capitalism is being used in it's true form, not the monopolistic leech fest we see called Capitalism today).

If you want to attack the conspiracy theory, that's fine and dandy. But if you do so in the future, at don't use false economic statements (easily debunked false economic statements).

Probably because anyone can make grammatical errors. I try to re-read before posting and correct the errors I notice, but I am far from perfect. How come people like you use fallacy to attack arguments instead using facts or debate?

geothermal energy comes from thermonuclear thorium reactions in the molten layers of the earth. thorium comes from supernovas thorium reactions come form the sun. so yes all energy comes from the sun, or more correctly the suns that existed before ours was formed.

The state didn't ban shit... the counties did. Personally I think it wasn't so much gas and oil companies, but your ex-neighbours being sick and tired of the pollution... not helped by the inevitable assholes who throw garbage in them.

That's the problem with the libertarian ideal, people are assholes... so it only works when your neighbours are really fucking far away. Which I imagine is the primary reason why you have less problems with your current state, lower population density.